When the 18-year-old Korean pianist Sunwook Kim won the Leeds International Piano competition in 2006, joining the likes of Murray Perahia, Radu Lupu and Artur Pizarro, he became the youngest ever player to do so. Such early success can prove dangerous to soloists' careers, but Kim has managed things sensibly, concentrating on his core repertoire of Beethoven, Schumann, Chopin and Brahms. He has also recorded the piano concerto by his compatriot Unsuk Chin. His Proms debut last year, with the Bournemouth Symphony Orchestra, showed him on promising form, with a maturity beyond his years.

If the beginning of his solo recital in the Stationers' Hall – as part of the City of London festival's Seoul in the City (groan) — had an impetuous feel to it that was entirely in keeping with the music. Kim began with Scriabin's third piano sonata, whose opening ba-boom figures in the bass sent shockwaves through the still-chattering audience. But the first movement, subtitled drammatico, was never overdone. The swell of suspended harmonies was perfectly controlled, the chords perfectly struck and voiced, and Kim always kept the sense of restless searching at just the right level of intensity – it's all too easy to sound just lost in this piece.

Similar dangers were encountered in César Franck's Prelude, Choral and Fugue, a work whose textures can sound turgid on modern pianos and whose sense of line and development can sound meandering. In its more delicate moments, though, it's a rewarding piece to play and hear, and Kim worked hard to keep the pace under control, allowing the joyous conclusion to yield its hard-won pleasures.

Kim concluded with Schumann's First Piano Sonata. Though it started well, with the left-hand's constant rocking motion beautifully controlled, its flowing phrases became increasingly submerged under the growing swell of passagework as the work progressed. There was less concentration here, too, perhaps due to the stifling heat. but everything points to the continuing rise of and exceptional maturity of this pianist, whose name is definitely one to keep in mind.